Low molecular weight polyphenylene ether compositions

Claim 2

A thermoplastic composition which, after molding, has good impact resistance, said composition comprising: (a) a low molecular weight polyphenylene ether resin, said resin having an intrinsic viscosity of less than 0.33 deciliters/gram when measured in solution in chloroform at 30° C.; (b) a styrene resin; and (c) an elastomeric block copolymer of the A-B-A 1 type, wherein terminal blocks A and A 1 are the same or different and are polymerized vinyl aromatic hydrocarbons and center block B is a polymerized conjugated diene, the molecular weight of B being higher than the combined molecular weights of A and A 1 .

Claim 3

A composition as defined in claim 1 wherein the polyphenylene ether resin (a) has an intrinsic viscosity of from about 0.1 to about 0.33 deciliters/gram when measured in solution in chloroform at 30° C.

Claim 4

A composition as defined in claim 1 wherein the polyphenylene ether resin (a) is comprised of structural units of the formula: ##STR4## wherein the oxygen ether atom of one unit is connected to the benzene nucleus of the next adjoining unit, n is a positive integer sufficient to provide an intrinsic viscosity no greater than 0.33 deciliters per gram in solution in chloroform at 30° C., each Q is a monovalent substituent selected from the group consisting of hydrogen, halogen, hydrocarbon radicals free of a tertiary alpha-carbon atom, halohydrocarbon radicals having at least two carbon atoms between the halogen atom and the phenyl nucleus, hydrocarbonoxy radicals and halohydrocarbonoxy radicals having at least two carbon atoms between the halogen atom and phenyl nucleus.

Claim 5

A composition as defined in claim 3 wherein each Q is alkyl having from 1 to 4 carbon atoms.

Claim 6

A composition as defined in claim 3 wherein said polyphenylene ether is poly(2,6-dimethyl-1,4-phenylene) ether.

Claim 7

A composition as defined in claim 1 wherein the styrene resin (b) is a homopolystyrene resin.

Claim 8

A composition as defined in claim 1 wherein the styrene resin (b) is a rubber modified high impact polystyrene resin.

Claim 9

A composition as defined in claim 1 wherein in A-B-A 1 block copolymer (c), each of terminal blocks A and A 1 has an average molecular weight of from about 2,000 to about 100,000 and center block B has an average molecular weight of from about 25,000 is about 1,000,000.

Claim 10

A composition as defined in claim 1 wherein the A-B-A 1 block copolymer (c) is hydrogenated.

Claim 11

A composition as defined in claim 1 wherein component (c) comprises from 1 to 99 parts by weight of an unhydrogenated A-B-A 1 block copolymer and from 99 to 1 parts by weight of an hydrogenated A-B-A 1 block copolymer.

Claim 12

A composition as defined in claim 9 wherein the average unsaturation of center block B has been reduced to less than 20% of its original value.

Claim 13

A composition as defined in claim 9 wherein in said hydrogenated A-B-A 1 block copolymer, each of terminal blocks A and A 1 has an average molecular weight of from about 4,000 to about 115,000 and center block B has an average molecular weight of from about 20,000 to about 450,000.

Claim 14

A composition as defined in claim 1 wherein in the A-B-A 1 block copolymer (c), the vinyl aromatic hydrocarbon of terminal blocks A and A 1 are selected from the group consisting of styrene, α-methyl styrene, vinyl toluene, vinyl xylene and vinyl naphthalene and the conjugated diene of center block B is selected from the group consisting of butadiene, isoprene, 1,3-pentadiene and 2,3-dimethylbutadiene.

Claim 15

A composition as defined in claim 1 which comprises from about 5 to about 95 parts by weight of polyphenylene ether resin (a), from about 95 to about 5 parts by weight of styrene resin (b) and from about 1 to about 25 parts by weight of A-B-A 1 block copolymer (c), based on 100 parts by weight of resinous components (a), (b) and (c).

Claim 16

A composition as defined in claim 1 which includes a reinforcing amount of a reinforcing agent.

Claim 17

A composition as defined in claim 15 wherein said reinforcing agent comprises fibrous glass.

Claim 18

A composition as defined in claim 1 which includes a flame retardant amount of a flame retardant agent.

Claim 19

A thermoplastic composition having good impact resistance after molding, which comprises: (a) from about 5 to about 95 parts by weight of a low molecular weight polyphenylene ether resin having an intrinsic viscosity of less than 0.33 deciliter per gram in solution in chloroform at 30° C.; (b) from about 95 to about 5 parts by weight of a styrene resin; and (c) from about 1 to about 25 parts by weight of an elastomeric block copolymer of the A-B-A 1 type in which terminal blocks A and A 1 are the same or different and are polymerized vinyl aromatic hydrocarbons and center block B is a polymerized conjugated diene, the molecular weight of B being higher than the combined molecular weights of A and A 1 .

Claim 20

A thermoplastic composition having good impact resistance after molding, which comprises: (a) from about 5 to about 95 parts by weight of a low molecular weight polyphenylene ether resin having an intrinsic viscosity of less than 0.33 deciliter per gram in solution in chloroform at 30° C.; (b) from about 95 to about 5 parts by weight of a styrene resin; and (c) from about 1 to about 25 parts by weight of an elastomeric block copolymer of the A-B-A 1 type in which terminal blocks A and A 1 are the same or different and are polymerized vinyl aromatic hydrocarbons and center block B is a polymerized conjugated diene, the molecular weight of B being higher than the combined molecular weights of A and A 1 .

Claim 21

A composition as defined in claim 1, which includes from 1 to about 80 parts by weight of a filamentous glass reinforcing agent.

Claim 22

A composition as defined in claim 1, which includes from 0.5 to 50 parts by weight of an aromatic carbonate homopolymeric flame retardant agent.